Process for the production of multi-colored woolen goods



United States Patent 3,310,361 PROCESS FOR THE PRODUCTION OF MULTI-COLORED WOOLEN GOODS John R. Stewart, Pointe Claire, Quebec, Canada,assignor to Gelgy Chemical Company, Greenburgh, N.Y., a corporation ofDelaware No Drawing. Filed Nov. 7, 1963, Ser. No. 322,071 14 Claims.(Cl. 8-15) This invention relates to the dyeing of woolen goods. Moreparticularly, the present invention pertains to a process for dyeingwoolen goods so as to obtain multicolored etfects and especiallytwo-tone or tone-on-tone effects with excellent light and wet fastness.

'Heret-ofore, woolen materials exhibiting multi-colored effects could beproduced only by first preparing dyed materials of different colors andthen weaving these into the desired color patterns. It is at onceobvious that such a dyeing method is involved and costly as it isnecessary to anticipate a multitudeof color combinations in advance,thereby creating large quantities of stock which, if color demandschange, may no longer be useful, or to bear the consequence of longdelays in deliveries because of the processing necessary to produce thedesired color patterns. According to another present practice forachieving two-tone effect, Woolen materials are treated so as to makesome residues of amino acids found in wool wholly or partially resistantto selected dyestuffs which normally dye wool (see Canadian Patent No.519,099, issued Dec. 6, 1955). The disadvantage which inheres in thismethod is the difiiculty of obtaining reproducible results and thelimitation to color effects in the nature of heather (ingrain ormelange) effects. Still another method which may be employed for limitedmulti: color dyeing o-f woolen materials is the chlorination method,i.e. the treatment of wool with hypochlorites and dyeing such wool incombination with untreated wool. Col-or effects by this method areproduced, however, at the expense of the durability and adequate wetfastness of the treated fibers.

In contrast thereto, it has now surprisingly been found that two-tonewoolen goods which are commercially acceptable and competitivelyproducible on a large scale and which are free of any of thedisadvantages enumerated above, can conveniently and readily be producedby a process which consists of a combination of sequential steps: firstthe pre-treatment of the given woolen material by mordanting with achromate o-r bichrornate fixed on the wool fiber by means of a sulfiteor bisulfite salt as reducing agent; secondly, the removal of unfixedchrome by rinsing; thirdly, the combining of the woolen materials sotreated withuntreated woolen materials; fourthly, the dyeing of thecomposite with a mordant dye or a combination of mordant dyes; andlastly, an aftertreatment which involves addition of the above chromemordants to the dyebath.

More specifically, the process of this invention contemplates first themordanting of woolen materials by an improved bottom chroming procedurewhich yields surprising and unexpected results. The woolen materials aretreated in an aqueous solution containing 0.5 to 2% and preferably notover 1.5 %on the weight of wool, of

a chromate, such as, potassium or sodium chromate or bichr-omate and anorganic or inorganic non-chelatin-g acid, preferably formic, acetic orsulfuric acids, giving a pH in the range of between 2 and 6 .andpreferably about 4.5 to maintain the wool in optimum condition. Theamount of the chromate used, as indicated by the above range of from 0.5to 2% on the weight of wool, is important: if less than 0.5% is employedan insuflicient amount of chrome may become fixed onto the fiber for3,310,361 Patented'Mar. 21, 1967 ICC production of heavy shades; if morethan 2% is used, the durability and quality of the wool may bedeleteriously affected. It has been found that 1.5% of the chromate ispreferable as it will insure complete chroming of the fiber even for theheaviest shades desired.

This mordanting treatment then involves boiling for from 30 to 60minutes and the subsequent additionof sodium or potassium sulfite orbisulfite as reducing agent in a concentration of fro-m 0.5 to 1%andpreferably 0.75 %on the weight of wool. The treatment is continued byfurther boiling for from 15 to 30 minutes until the appearance of thewool fiber is a uniform greenishgray (without a yellowish tint)indicating the substantially complete fixation of the chrome on thefiber The presence of any of the above reducing agents is critical as itserves the purpose of substantially completing the re-' duction of thechrome in hexavalent form to its trivalent cationic stable form formaximum mordanting action and to minimize the migration of unreduced(labile) chrome to the untreated Wool in the subsequent cross-dyeingoperation. The advantages achieved thereby are substantial reduction ofstaining of the untreated woolen material by the mordant dyestutf andreproducibility from lot to lot in subsequent dyeing. The amount ofreducing agent used is also important: if less than 0.5% on the weightof wool is used incomplete reduction and fixation of the chrome will beachieved, if more than 1% is em ployed, however, the cystine linkages ofthe wool fiber may be deleteriously affected.

After the above-described mordanting procedure is concluded, thematerial treated must be rinsed thoroughly in water at approximately F.to remove any unfixed chrome present. The material is subsequentlydried.

The wo-olen materials so treated can then be combined in Whatever formis suitable (e.g. by carding, combing, spinning, twisting, and notablyweaving, knitting, tufting, assembling, etc.) with untreated woolenmaterials as a second step.

It is then possible to dye the composite thus obtained with a mordantdye or a combination of mordant dyes. This dyeing procedure, forinstance, involves the preparation of a dye bath at a temperature offrom 100 to F. containing from 5 to 10% on the weight of the wool ofanhydrous Glauberssalt, sufiicient acetic acid (or any other organic orinorganic non-chelating acids, such as, formic acid, sulfuric acid,etc.) to obtain a pH of 2 to 6, and 0.5 to 2% of Tinegal Wa condensateof stearyl diethylene triamine and ethylene oxide. In addition toTinegal W, Irgasol SW, the condensate of N -stearyl-N N -bis-(fi-phenolhydroxyethyl)-diethylene triamine and ethylene oxide may also be used toparticular advantage. (See Example 3, Belgian Patent 592,741.) Thisliquor is then circulated for from 10 to 15 minutes and any of thedesired mordant dyes-or combinations thereof is dissolved and added. Thetemperature of the dye bath is then raised to the boil and it is boiledfor from 30 to 60 minutes.

Mordant dyes, and particularly chrome dyes which can be employed in thepractice of this invention are illustrated in the examples below.Further chrome dyes that can be used are the following:

C.I. Mordant Black 1 (Color Index No. 15710) C.-I. Mordant Black 9(Color Index No. 16500) C.I. Mordant Black 13 (Color Index No. 63615)C.I. Mordant Black 17 (Color Index No. 15705 C.I. Mordant Black 38(Color Index No. 18160) C.I. Mordant Blue 9 (Color Index No. 14855 CI.Mordant Blue 47 (Color Index No. 43855) C.'I. Mordant Brown 1 (ColorIndex No. 20110) C.I. Mordant Brown 19 (Color Index No. 14250) C.I.Mordant Brown 23 3 C.I. Mordant Brown 33 (Color Index No. 13250) C.I.Mordant Brown 40 (Color Index No. 17590) C. I. Mordant Brown 63 C.I.Mordant Orange 1 (Color Index No. 14030) C.I. Mordant Orange C.I.Mordant Orange 6 (Color Index No. 26520) C.I. Mordant Red 3 (Color IndexNo. 58005) C.I. Mordant Red 17 (Color Index No. 18750) C.I. MordantViolet 28 (Color Index No. 43570) C.I. Mordant Yellow 14 (Color IndexNo. 14055) C.I. Mordant Yellow 30 (Color Index No. 18710) The employmentof one or more fast wool colors or the acid type in conjunction with theabove-mentioned chrome colors brings about an extension of the contrastrange obtainable by means of the chrome colors themselves and alsoserves in practice the important purpose of permitting shadingcorrections and alterations of a minor nature to be effected once themajor contrast has been established by means of chrome colors. Aciddyestuffs suitable for such purposes should be selected from those thatare fast to chrome well known in the art, that is to say, those which donot suffer any adverse change on either shade or fastness properties bythe subsequent top chroming procedure.

For example, acid dyes of the following groups may be used:

1. 1:2 pre-metallized acid dyes (i.e. one atom of metal complexed withtwo molecules of dyestuff) normally applied from weak acid solutions, pH6.

2. Acid dyes which are normally applied with weak acids of a pH of 4.5to 6.

3. Fibre reactive dyes which are normally applied to wool from weak acidbaths (pH 3 to 5).

The above dyestuffs whether mordant or acid, may be used in any of thefollowing concentrations: 0.001% to 6% depending on the shade of colordesired and the strength of the dyestuffs used.

The after-treatment then involves an addition to the dyebath of between0.1 and 1.5% and preferably about 0.25 to 1% of a chromate, such assodium or potassium chromate or dichromate. This addition is made afterthe mordant dye or combination of mordant dyes has been exhausted ontothe composite of treat-ed and untreated woolen material; it serves thepurpose of topchroming the mordant dye present on the untreated fiber,converting this dye into an insoluble metal lake. After this addition,boiling is continued for another 30 to 60 minutes. Certain selectedmordant dyes, well known in the art, for example, such as are applicableby meta-chrome dyeing methods, permit the simultaneous presence ofmordant in the application bath. In such cases it is possible to add themordant to the dye bath at the beginning of the dyeing operation. Bymaking an addition of mordant to the dye bath in either or both of theabove ways an increased all-round fastness, particularly, light and wetfastness, of the unmordanted portion of the composite is achieved.

Lastly, the dyed woolen goods are rinsed in a fresh bath at 100 to 120F. for approximately 15 minutes and dried.

The following examples will illustrate the invention in greater detail,but should be taken to limit the invention in any way. The percentagesgiven are percentages by weight calculated on the weight of wool.

A. MORDANTING PROCEDURE Example I Wool yarn was treated in a dyeingvessel at a liquor ratio of 25 parts of water to one part of wool.Sodium bichromate (1.5%) and 2% of formic acid 85%, were added. This wasboiled for 45 minutes and 0.75% of sodium bisulfite was then added andthe boiling continued for 15 minutes. The yarn was then rinsed in waterat F. and dried.

B. COMBINING THE TREATED AND UNTREATED WOOLEN MATERIALS Example 11 A dyebath was prepared at a temperature of F. with 10% of Glaubers salt,anhydrous, 3% of acetic acid 56% and 0.5% of Irgasol SW. The liquor wascirculated for 10 minutes and 0.04% of C.I. Mordant Black 13 (ColorIndex No. 63615) and 0.01% of C.I. Mordant Violet 28 (Color Index No.43570) were dissolved in water and added. The temperature was raised tothe boil and the liquor was boiled for 30 minutes. Then 0.5% of sodiumbichromate was added and the boiling continued for another 45 minutes.The fabric was then rinsed in a fresh bath at 100 F for 15 minutes anddried.

A fabric having dark gray and light gray shades was obtained, thepre-treated yarn exhibiting the darker shade.

In the following examples the procedure of Example II was repeated withthe substitution, however, of other mordant dyes to obtain various othertwo-tone effects.

Example III A dark green (pre-treated yarn) and light green fabric wasobtained.

Example IV Percent C.I. Mordant Violet 1 (Color Index No. 43565) 0.50Acetic acid 56% 2.00 Glaubers salt 10.00 Irgasol SW 0.25

A violet (treated yarn) and bluish grey fabric was obtained.

Example V Percent C.I. Mordant Orange 8 1.00 Irgasol SW 0.25 Glauberssalt 10.00 Acetic acid 56% 2.00

A dark orange (treated yarn) and light pink fabric was. obtained.

Example VI w Percent C.I. Mordant Blue 1 (Color Index No. 43830) 0.50Glaubers salt 10.00 Irgasol SW 0.125 Formic acid 85% 1.00

A dark royal blue (treated yarn) and bluish grey fabric was obtained.

Example VII Percent C.I. Mordant Green 5 0.50 Glaubers salt 10.00Irgasol SW 0.25

Acetic acid 56% 2.00

'trast color effects.

form can be spun into singles yarn and used either as A dark green(treated yarn) and light green fabric was obtained.

Example VIII 1 Percent C.I. Mordant Green 26 (Color Index No. 18180)0.75 Glaubers salt 10.00 Formic acid 85% 2.00 Tiuegal W 0.50

A heavy olive-green (treated yarn) and light blue-grey fabric wasobtained.

Example IX Percent ClI. Mordant Red 7 (Color Index No. 18760) 0.75Glaubers salt 10.00 Tine-gal W 0.50 Acetic acid 56% 2.00

A heavy bordeaux (treated yarn) and pink fabric was obtained.

The CI. Acid Yellow 79 in this formula is not chromed but produces afastyellow shading component on the untreated wool and the top chromingprocedure intensifies this contrast as well as producing the bestall-round fastness of the composite. A grey green (chromed) and beige(unchromed) contrast pattern is obtained.

It will be readily appreciated by skilled colorists that the aboveexamples are merely illustrative and that numerous other colorcombinations can easily be achieved.

Further interesting color combinations exhibiting threecolor effectshave been produced by combining treated and untreated woolen materials,described above, with woolen materials which have been separately dyedor pre dyedwith fastness to cross dyeing-in very dark shades, such as,black, deep navy blue, dark .brown and dark green. The resultingcomposite is then piece-dyed.

It is alsoreadily apparent to men skilled in the art that g theabove-described mordanting and dyeing procedure may be applied to woolenmaterials in any form. For example, wool in loose form, i.e. raw stock,can be so treated and combined with loose untreated wool and dyed inloose form or spun into yarn and dyed or the yarn thus obtained can beconverted to fabric and then dyed. Such fibers, yarns or fabrics exhibitheather color effects. Furthermore, wool in loose form which has been sotreated, can be spun into singles yarn and plied with untreated yarnsand dyed in yarn form or incorporated in a fabric and piece-dyed. Theseyarns or fabrics given con- In addition, treated wool in loose singlesor plied yarn to be made into fabrics together with untreated yarn andthen piece-dyed to give multi-color or two-tone effects as indicated andshown above.

Altcrnately, woolen materials in yarn form can be processed inaccordance with this invention and treated singles yarns can be pliedwith untreated singles and yarn dyed novelty fleck and slub yarfi. Theseare likewise within the scope of the present invention.

' What is claimed is:

1. A process for producing multi-colored woolen goods which comprisestreating woolen material by boiling in an aqueous solution containing0.5 to 2% on the weight of wool of a chromate selected from the groupconsisting of sodium and potassium chromate and bichromate, 0.5 to 1% onthe weight of wool of a reducing agent selected from the groupconsisting of sodium and potassium sulfite and bisulfite and anon-chelating acid giving a pH in the range of between 2 and 6, rinsingthe mordanted Woolen material, combining the woolen material so treatedwith untreated Woolen material, dyeing the composite in a dye bathcontaining at least one mordant dye and adding to said dyebath whenexhausted 0.1 to 1.5% on the weight of wool of the said chromate.

2. A process according to claim 1 wherein 1.5%-on the weight of wool ofthe chromate and 0.75% on the weight of Wool of the reducing agent ispresent in said solution and wherein 0.25 to 1% on the weight of wool ofthe chromate is added to said dyebath.

3. A process according to claim 1 wherein said composite is dyed in adye bath which contains also at least one acid dye.

4. A process for producing multi-colored Woolen goods which comprisestreating woolen material by boiling in an aqueous solution containing0.5 to 2% on the weight of wool of a chromate selected from the groupconsisting of sodium and potassium chromate and bichromate, 0.5 to 1% onthe weight of wool of a reducing agent selected from the groupconsisting of sodium and potassium sulfite and bisulfite and anon-chelating acid giving a pH in the range of between 2 and 6, rinsingthe mordanted woolen material, combining the Woolen material so treatedwith untreated woolen material, dyeing the composite by boiling in a dyebath containing at least one mordant dye and 0.1 to 1.5 on this weightof wool of said chromate.

5. A process according to claim 3 wherein 1.5% on the weight of wool ofthe chromate and 0.75% on the weight of wool of the reducing agent ispresent in said solution and wherein 0.25 to 1% on the weight of wool ofthe chromate is added to said dye bath.

6. A process according to claim 4 wherein said composite is dyed in adye bath which contains also at least one acid dye.

7. A process for producing multi-colored woolen goods which comprisesmordanting woolen material by boiling in an aqueous solution containing0.5 to 2% on the weight of wool of a chromate selected from the groupconsisting of sodium and potassium chromate and bichromate and anon-chelating acid giving a pH in the range of between 2 and 6, addingto said solution 0.5 to 1% on the weight of Wool of a reducing agentselected from the group consisting of sodium and potassium sulfite andbisulfite, continuing said boiling, rinsing the mordanted woolenmaterial thoroughly with water of about F., combining the woolenmaterial so treated with untreated woolen material, dyeing the compositeby boiling in a dyebath containing at least one mordant dye and adding0.1 to 1.5 on the weight of wool of the said chromate to the dye bathwhen exhausted and continuing said boiling.

8. A process according to claim 5 wherein 1.5% on the Weight of wool ofthe chromate and 0.75% on the Weight of wool of the reducing agent ispresent in said solution and wherein 0.25 to 1% on the weight of wool ofthe chromate is added to said dye bath.

9. A process according to claim 7 wherein said composite is dyed in adye bath which contains also at least one acid dye.

10. A process for producing multi-colored woolen goods which comprisesmordanting woolen material by boiling in an aqueous solution containing0.5 to 2% on the weight of wool of a chromate selected from the groupconsisting of sodium and potassium chromate and bichromate and anon-chelating acid giving a pH in the range of between 2 and 6, addingto said solution 0.5 to 1% on the weight of wool of a reducing agentselected from the group consisting of sodium and potassium sulfite andbisulfite, continuing said boiling, rinsing the mordanted woolenmaterial thoroughly with water of about 100 F., combining the woolenmaterial so treated with untreated woolen material, dyeing the compositeby boiling in a dye bath comprising at least one mordant dye and 0.1 to1.5% on the weight of wool of said chromate.

11. A process according to claim 7 wherein 1.5 on the weight of wool ofthe chromate and 0.75 on the weight of wool of the reducing agent ispresent in said solution and wherein 0.25 to 1% on the weight of wool ofthe chromate is added to said dye bath.

12. A process according to claim 10 wherein said composite is dyed in adye bath which contains also at least one acid dye.

13. A process for producing multi-colored woolen goods which comprisesmordanting woolen material by boiling in an aqueous solution containing1.5% on the weight of wool of sodium bichrornate and about 2% on theweight of wool of formic acid, adding to said solution 0.75% on theweight of Wool of sodium bisulfite as reducing agent, continuing saidboiling until the woolen material is uniformly greenish-grey, rinsingthe mordanted woolen material thoroughly with water of about 'F.,combining the woolen material so treated with untreated woolen material,dyeing the composite by boiling in a dyebath containing at least onemordant dye and adding 0.5% on the weight of wool of the said sodiumbichromate tothe dyebath when exhausted, continuing said boiling andthen rinsing and drying said composite.

14. A process according to claim 13 wherein said composite is dyed in adye bath which contains also at least one acid dye.

References Cited by the Examiner UNITED STATES PATENTS 670,959 4/1901Kick 815 689,559 12/1901 Meyer 815 3,006,935 10/1961 Albrecht 861 OTHERREFERENCES Townend, 1., Soc. Dyers & Col., June 1945, pp. 144-149.

Knecht, A., Manual of Dyeing, 9th ed., vol. 1, pp. 251- 259, pub. 1945by Mapleton House, publ., Brooklyn 4, New York.

NORMAN G. TORCHIN, Primary Examiner.

T. J. HERBERT, Assistant Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent Nou3,310,361 March 21, 1967 John R, Stewart e above numbered pat- It ishereby certified that error appears in th Patent should read as entrequiring correction and that the said Letters corrected below.

In the heading to the printed specification, line 5, for "Geigy ChemicalCompany Signed and sealed this 7th day of November 1967.

(SEAL) Attest:

EDWARD J. BRENNER Edward M. Fletcher, Jr.

Commissioner of Patents Attesting Officer read Geigy ChemicalCorporation

1. A PROCESS FOR PRODUCING MULTI-COLORED WOOLEN GOODS WHICH COMPRISESTREATING WOOLEN MATERIAL BY BOILING IN AN AQUEOUS SOLUTION CONTAINING0.5 TO 2% ON THE WEIGHT OF WOOL OF A CHROMATE SELECTED FROM THE GROUPCONSISTING OF SODIUM AND POTASSIUM CHROMATE AND BICHROMATE, 0.5 TO 1% ONTHE WEIGHT OF WOOL OF A REDUCING AGENT SELECTED FROM THE GROUPCONSISTING OF SODIUM AND POTASSIUM SULFITE AND BISULFITE AND ANON-CHELATING ACID GIVING A PH IN THE RANGE OF BETWEEN 2 TO 6, RINSINGTHE MORDANTED WOOLEN MATERIAL, COMBINING THE WOOLEN MATERIAL SO TREATEDWITH UNTREATED WOOLEN MATERIAL, DYEING THE COMPOSITE IN A DYE BATHCONTAINING AT LEAST ONE MORDANT DYE AND ADDING TO SAID DYEBATH WHENEXHAUSTED 0.1 TO 1.5% ON THE WEIGHT OF WOOL OF THE SAID CHROMATE.